CN111198381B - Laser radar ranging system - Google Patents
Laser radar ranging system Download PDFInfo
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- CN111198381B CN111198381B CN201811376651.5A CN201811376651A CN111198381B CN 111198381 B CN111198381 B CN 111198381B CN 201811376651 A CN201811376651 A CN 201811376651A CN 111198381 B CN111198381 B CN 111198381B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
- G01S17/02—Systems using the reflection of electromagnetic waves other than radio waves
- G01S17/06—Systems determining position data of a target
- G01S17/08—Systems determining position data of a target for measuring distance only
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
- G01S7/4802—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00 using analysis of echo signal for target characterisation; Target signature; Target cross-section
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A90/00—Technologies having an indirect contribution to adaptation to climate change
- Y02A90/10—Information and communication technologies [ICT] supporting adaptation to climate change, e.g. for weather forecasting or climate simulation
Abstract
The invention relates to a laser radar ranging system. The system comprises an optical detector, a variable gain amplifier, a converter, a digital time gain controller and a main controller, wherein the optical detector is connected with the variable gain amplifier; the optical detector adjusts the gain of the first echo signal according to the bias control signal output by the main controller to obtain a second echo signal; the variable gain amplifier adjusts the gain of the second echo signal according to the gain value output by the main controller to obtain a third echo signal; and the digital time gain controller adjusts the gain of the third echo signal according to the gain coefficient output by the main controller. The system improves the ranging performance of the laser radar ranging system by adjusting the gain of the echo signal on the receiving link.
Description
Technical Field
The invention relates to the field of laser radars, in particular to a laser radar ranging system.
Background
The laser radar ranging has strong adaptability to the external environment, and is widely applied to the fields of automatic driving, auxiliary driving, environmental perception and the like. However, the detection distance of the laser radar is large, and the difference of the reflectivity of different objects in the sensed environment is large, so that the dynamic range of signals to be processed by the laser radar is also large.
The traditional method for solving the problem of overlarge dynamic range of signals processed by the laser radar is mainly realized by adopting automatic power control, namely, closed-loop control is formed between transmitting and receiving, the transmitting power of each time is correspondingly adjusted according to the received echo energy in the previous transmitting period, the transmitting power of the laser radar signals in the next period is reduced when the received echo energy is too high, and the transmitting power of the laser radar signals in the next period is improved when the received echo energy is too low.
However, the conventional method for solving the problem of overlarge dynamic range of signals processed by the laser radar has the problems of high complexity of a transmitting circuit and low ranging precision.
Disclosure of Invention
Therefore, it is necessary to provide a laser radar ranging system aiming at the problems of high complexity of a transmitting circuit and low ranging accuracy of the traditional solution.
A lidar ranging system comprising: the optical detector is connected with the variable gain amplifier, the converter is respectively connected with the variable gain amplifier and the digital time gain controller, and the main controller is respectively connected with the optical detector, the variable gain amplifier and the digital time gain controller; wherein the content of the first and second substances,
the optical detector is used for adjusting the gain of the first echo signal according to the bias control signal output by the master controller to obtain a second echo signal;
the variable gain amplifier is used for adjusting the gain of the second echo signal according to the gain value output by the main controller to obtain a third echo signal;
and the digital time gain controller is used for adjusting the gain of the third echo signal according to the gain coefficient output by the main controller.
In one embodiment, the main controller is used for determining the gain value according to a preset distance-gain compensation curve or the statistical characteristics of echo signals; the statistical characteristics include amplitude information of the echo signal and waveform information of the echo signal.
In one embodiment, the system further comprises a digital pre-processing module, which is respectively connected with the converter and the digital time gain controller;
the digital preprocessing module is used for performing echo shaping processing on the third echo signal; the echo shaping process includes a familiar filtering process and a baseline correction process.
In one embodiment, if the variable gain amplifier is an analog controlled variable gain amplifier, the converter includes an analog-to-digital converter and a digital-to-analog converter;
the input end of the analog-to-digital converter is connected with the output end of the variable gain amplifier, and the output end of the analog-to-digital converter is connected with the input end of the digital preprocessing module;
the input end of the digital-to-analog converter is connected with the main controller, and the output end of the digital-to-analog converter is connected with the input end of the variable gain amplifier.
In one embodiment, if the variable gain amplifier is a digitally controlled variable gain amplifier, the converter comprises an analog-to-digital converter; the input end of the analog-to-digital converter is connected with the main controller, and the output end of the analog-to-digital converter is connected with the input end of the digital preprocessing module.
In one embodiment, the main controller is configured to determine the gain factor according to a gain compensation curve or a statistical characteristic of the echo signal.
In one embodiment, the gain compensation curve is a curve obtained according to a theoretical optical path attenuation curve or a calibrated optical path attenuation curve.
In one embodiment, the main controller is configured to generate the bias control signal based on a characteristic of the light detector and an optical path attenuation characteristic; the characteristics of the photodetector are indicative of a relationship between a received optical power of the photodetector and a bias control signal.
In one embodiment, the system further comprises a bias controller connected to the main controller and the light detector, respectively;
the bias controller is used for generating an external bias voltage according to the bias control signal output by the main controller and applying the external bias voltage to the light detector;
the photodetector adjusts the gain of the first echo signal according to the applied bias voltage.
In one embodiment, the system further comprises a ranging module connected to the digital time gain controller;
and the ranging module is used for acquiring ranging information according to the output signal of the digital time gain controller.
The laser radar ranging system comprises an optical detector, a variable gain amplifier, a converter, a digital time gain controller and a main controller, wherein the optical detector is connected with the variable gain amplifier, the converter is respectively connected with the variable gain amplifier and the digital time gain controller, the main controller is respectively connected with the optical detector, the variable gain amplifier and the digital time gain controller, the optical detector adjusts the gain of a first echo signal according to a bias control signal output by the main controller to obtain a second echo signal, the variable gain amplifier adjusts the gain of the second echo signal according to a gain value output by the main controller to obtain a third echo signal, and the digital time gain controller controls the gain of the third echo signal according to a gain coefficient output by the main controller. According to the laser radar ranging system, the optical detector, the variable gain amplifier and the digital time gain controller are respectively controlled by the main controller on the receiving link to adjust the gain of the echo signal, so that the dynamic range of the laser radar system is improved, the ranging capability and the ranging precision of the laser radar ranging system are further improved, and the difficulty of hardware design of a transmitting link is simplified; in addition, the adjustment of the gain of the echo signal on a receiving link has better real-time performance, and the ranging performance of the laser radar ranging system is improved.
Drawings
FIG. 1 is a schematic diagram of a lidar ranging system provided in one embodiment;
FIG. 2 is a schematic diagram of a lidar ranging system according to another embodiment;
FIG. 3 is a schematic diagram of a lidar ranging system according to another embodiment;
FIG. 4 is a schematic diagram of a lidar ranging system according to another embodiment;
FIG. 5 is a schematic diagram of a lidar ranging system according to another embodiment;
FIG. 6 is a schematic diagram of a lidar ranging system according to another embodiment;
fig. 7 is a schematic diagram of a lidar ranging system according to another embodiment.
Description of reference numerals:
a light detector 100; a variable gain amplifier 200; a converter 300;
an analog-to-digital converter 301; a digital-to-analog converter 302; a digital time gain controller 400;
a main controller 500; a digital pre-processing module 600; a bias controller 700;
a ranging module 800.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.
The traditional method for solving the problem of overlarge dynamic range of signals processed by the laser radar mainly adopts automatic power control, namely closed-loop control is formed between transmitting and receiving, and the transmitting power of each time is correspondingly adjusted according to the echo energy received in the previous transmitting period. Therefore, the embodiment of the invention provides a laser radar ranging system, aiming at solving the technical problems in the prior art.
The following describes the technical solution of the present invention and how to solve the above technical problems in detail by using specific examples. The following several specific embodiments may be combined with each other, and details of the same or similar concepts or processes may not be repeated in some embodiments. Embodiments of the present invention will be described below with reference to the accompanying drawings.
Fig. 1 is a schematic diagram of a lidar ranging system according to an embodiment. As shown in fig. 1, the laser radar ranging system includes: the optical detector 100 is connected with the variable gain amplifier 200, the converter 300 is respectively connected with the variable gain amplifier 200 and the digital time gain controller 400, and the main controller 500 is respectively connected with the optical detector 100, the variable gain amplifier 200 and the digital time gain controller 400; the optical detector 100 is configured to adjust a gain of the first echo signal according to the bias control signal output by the main controller 500, so as to obtain a second echo signal; the variable gain amplifier 200 is configured to adjust a gain of the second echo signal according to the gain value output by the main controller 500, so as to obtain a third echo signal; the digital time gain controller 400 is configured to adjust the gain of the third echo signal according to the gain factor output by the main controller 500.
Specifically, the optical detector 100 is connected to the variable gain amplifier 200, and the optical detector 100 is also referred to as a laser receiver, and is configured to receive a first echo signal transmitted by the laser radar, convert the first echo signal from an optical signal to a current signal, adjust a gain of the first echo signal by changing an applied bias value according to a bias control signal output by the main controller 500, obtain a second echo signal, and transmit the second echo signal to the variable gain amplifier 200, where it is to be noted that the second echo signal transmitted to the variable gain amplifier 200 by the optical detector 100 is a converted current signal. Alternatively, the photodetector 100 may be any one of a diode, a diode array, a silicon photomultiplier, and a silicon photomultiplier array, and the diode may be an indium phosphide photodiode or an avalanche breakdown photodiode. Optionally, the diode array and the silicon photomultiplier array may be regular arrays, for example, in the diode array or the silicon photomultiplier array, the pitch between adjacent diodes or silicon photomultipliers may be a fixed value of 0.2mm or 0.5mm, etc. Optionally, the diode array and the silicon photomultiplier array may be circular arrays or irregular arrays.
The variable gain amplifier 200 is connected to the optical detector 100 and the converter 300, respectively, and the variable gain amplifier 200 is configured to convert a current signal sent by the optical detector 100 into a voltage signal, amplify and gain-compensate the converted voltage signal, and provide a signal amplitude in a reasonable range for the converter 300, specifically, the variable gain amplifier 200 compensates a gain of the received second echo signal according to a gain value output by the main controller 500, so as to obtain a third echo signal, and transmits the third echo signal to the converter 300. Alternatively, the variable gain amplifier 200 may be an analog controlled variable gain amplifier, or may be a digitally controlled variable gain amplifier.
The converter 300 is connected to the variable gain amplifier 200 and the digital time gain controller 400, respectively, and the converter 300 is configured to implement conversion between an analog signal and a digital signal and transmit the converted digital signal to the digital time gain controller 400, that is, the third echo signal received by the converter 300 is an analog signal, and the third echo signal transmitted to the digital time gain controller 400 is a converted digital signal, and optionally, an interface of the converter 300 may be a parallel port, or may be a high-speed serial interface such as LVDS or JESD.
The digital time gain controller 400 is connected to the converter 300, and the digital time gain controller 400 adjusts the gain of the third echo signal output by the converter 300 according to the gain factor output by the main controller 500. Optionally, the Digital time gain controller 400 may be a Field Programmable Gate Array (FPGA) controller or a Digital Signal Processor (DSP). Alternatively, the digital time gain controller 400 may adjust the gain of the third echo signal through a multiplier provided in the digital time gain controller. Optionally, the digital time gain controller 400 may further perform some processing, such as saturation processing or truncation processing, on the adjusted third echo signal to improve the accuracy of the gain-adjusted third echo signal.
The main controller 500 is connected to the optical detector 100, the variable gain amplifier 200, and the digital time gain controller 400, and the main controller 500 controls the optical detector 100 to adjust the gain of the first echo signal according to the output bias control signal, controls the variable gain amplifier 200 to adjust the gain of the second echo signal according to the output gain value, and controls the digital time gain controller 400 to adjust the gain of the third echo signal according to the output gain factor.
In the prior art, aiming at the problem that the dynamic range of signals required to be processed by a laser radar is too large, automatic power control is mainly adopted to solve the problem, closed-loop control is formed between transmitting and receiving, and transmitting power at each time is correspondingly adjusted according to echo energy received in a previous transmitting period.
In this embodiment, the lidar ranging system includes a photodetector, a variable gain amplifier, a converter, a digital time gain controller, and a main controller, the photodetector is connected to the variable gain amplifier, the converter is connected to the variable gain amplifier and the digital time gain controller, the main controller is connected to the photodetector, the variable gain amplifier, and the digital time gain controller, respectively, the photodetector adjusts a gain of the first echo signal according to a bias control signal output by the main controller to obtain a second echo signal, the variable gain amplifier adjusts a gain of the second echo signal according to a gain value output by the main controller to obtain a third echo signal, the digital time gain controller controls a gain of the third echo signal according to a gain factor output by the main controller, the lidar ranging system controls the photodetector, the digital time gain controller, and the digital time gain controller on a receiving link through the main controller, respectively, The variable gain amplifier and the digital time gain controller adjust the gain of the echo signal, and under the condition that the transmitting power is not changed, the dynamic range of the echo signal to be processed by the laser radar system is improved, so that the ranging precision of the laser radar ranging system is improved, and the difficulty of the hardware design of a transmitting link is simplified; in addition, the adjustment of the gain of the echo signal on a receiving link has better real-time performance, and the ranging performance of the laser radar ranging system is improved.
In the scenario that the variable gain amplifier 200 adjusts the gain of the second echo signal according to the gain value output by the main controller 500, the main controller 500 is configured to determine the gain value according to a preset distance-gain compensation curve or a statistical characteristic of the echo signal; the statistical characteristics include amplitude information of the echo signal and waveform information of the echo signal.
Specifically, the main controller 500 may determine, according to a preset distance-gain compensation curve and according to a distance value of the target object, a gain value corresponding to adjustment of the second echo signal in the process of receiving the echo signal by the laser receiver, and output the determined gain value to control the variable gain amplifier 200 to adjust the gain of the second echo signal; alternatively, the main controller 500 may determine that the variable gain amplifier 200 adjusts the gain value of the second echo signal based on the amplitude information of the echo signal and the waveform information of the echo signal. Optionally, if the amplitude of the echo signal is higher and the waveform of the echo signal is larger, the main controller 500 may decrease the output gain value; the main controller 500 may increase the output gain value if the waveform of the echo signal is smaller as the amplitude of the echo signal is lower.
In this embodiment, the main controller determines to adjust a gain value of the second echo signal according to a preset distance-gain compensation curve or a statistical characteristic of the echo signal, controls the variable gain amplifier to adjust a gain of the second echo signal, and under the condition that the transmission power is not changed, the variable gain amplifier improves a dynamic range of the echo signal to be processed by the laser radar system by adjusting the gain of the second echo signal in real time, so that the ranging accuracy of the laser radar ranging system is improved, and the ranging performance of the laser radar ranging system is improved.
Fig. 2 is a schematic diagram of a lidar ranging system according to another embodiment. As shown in fig. 2, the system further includes a digital pre-processing module 600, wherein the digital pre-processing module 600 is connected to the converter 300 and the digital time gain controller 400 respectively; the digital preprocessing module 600 is configured to perform echo shaping processing on the third echo signal; the echo shaping process includes a digital filtering process and a baseline correction process.
The filtering process is to extract a useful signal from the third echo signal and filter out a signal containing a measurement error and other interference. The filtering process may be a wiener filtering process or a kalman filtering process, the digital preprocessing module 600 may be a filter, for example, a high-pass filter, and the digital preprocessing module 600 may also be a low-pass filter or a band-pass filter.
Specifically, the laser radar ranging system further includes a digital preprocessing module 600, the digital preprocessing module 600 is respectively connected to the converter 300 and the digital time gain controller 400, the digital preprocessing module 600 receives a third echo signal sent by the converter 300, performs digital filtering processing and baseline correction processing on the third echo signal, extracts a useful echo signal from the third echo signal, filters out an echo signal containing a measurement error and other interferences from the third echo signal, and sends the third echo signal after the digital filtering processing and the baseline correction processing to the digital time gain controller 400.
In this embodiment, the lidar ranging system further includes a digital preprocessing module, the digital preprocessing module is respectively connected to the converter and the digital time gain controller, the digital preprocessing module performs digital filtering processing and baseline correction processing on the third echo signal transmitted by the converter, filters out echo signals containing measurement errors and other interferences in the third echo signal, sends the third echo signal after the filtering processing and the baseline correction processing to the digital time gain controller, performs the filtering processing and the baseline correction processing on the third echo signal through the digital preprocessing module under the condition that the transmission power is not changed, filters out signals containing the measurement errors and other interferences in the third echo signal, improves the accuracy of the third echo signal received by the digital time gain controller, and improves the ranging accuracy of the lidar ranging system, the ranging performance of the laser radar ranging system is improved.
Fig. 3 is a schematic diagram of a lidar ranging system according to another embodiment. As shown in fig. 3, if the variable gain amplifier 200 is an analog controlled variable gain amplifier, the converter 300 includes an analog-to-digital converter 301 and a digital-to-analog converter 302; the input end of the analog-to-digital converter 301 is connected with the output end of the variable gain amplifier 200, and the output end of the analog-to-digital converter 301 is connected with the input end of the digital preprocessing module 600; the input end of the digital-to-analog converter 302 is connected to the main controller 500, and the output end of the digital-to-analog converter 302 is connected to the input end of the variable gain amplifier 200.
Specifically, if the variable gain amplifier 200 is an analog controlled variable gain amplifier, the signal transmitted and received by the analog controlled variable gain amplifier is an analog signal, and the signal transmitted by the main controller 500 is a digital signal, so in this system, the converter 300 is required to convert the analog signal and the digital signal. The digital-to-analog converter 302 converts the digital signal of the gain value output by the main controller 500 into an analog control signal and sends the analog control signal to the analog control variable gain amplifier 200, and the analog control variable gain amplifier 200 adjusts the gain of the second echo signal according to the received analog control signal to obtain a third echo signal; the analog-to-digital converter 301 may convert an analog signal of the third echo signal sent by the analog-controlled variable gain amplifier 200 into a digital signal of the third echo signal, and send the digital signal of the third echo signal to the digital preprocessing module 600.
In this embodiment, if the variable gain amplifier in the lidar ranging system is an analog control variable gain amplifier, the converter includes an analog-to-digital converter and a digital-to-analog converter, the analog-to-digital converter converts an analog signal of the analog control variable gain amplifier into a digital signal and sends the digital signal to the digital preprocessing module, the digital-to-analog converter converts a digital control signal sent by the main controller into an analog control signal and sends the analog control signal to the analog control variable gain amplifier, thereby completing the adjustment of the gain of the analog control variable gain amplifier, when the distance is short, the main controller controls the analog control variable gain amplifier to reduce the gain, when the distance is long, the main controller controls the analog control variable gain amplifier to increase the gain, when the transmission power is not changed, the main controller adjusts the gain of the second echo signal through the analog control variable gain amplifier, the dynamic range of echo signals to be processed by the laser radar system is improved, the ranging precision of the laser radar ranging system is improved, and the ranging performance of the laser radar ranging system is improved.
Fig. 4 is a schematic diagram of a lidar ranging system according to another embodiment. As shown in fig. 4, if the variable gain amplifier 200 is a digitally controlled variable gain amplifier, the converter 300 includes an analog-to-digital converter 301; the input end of the analog-to-digital converter 301 is connected to the main controller 500, and the output end of the analog-to-digital converter 301 is connected to the input end of the digital preprocessing module 600.
Specifically, if the variable gain amplifier 200 is a digitally controlled variable gain amplifier, the main controller 500 may directly control the digitally controlled variable gain amplifier 200 to adjust the gain of the second echo signal through a digital interface of the digitally controlled variable gain amplifier 200 to obtain a third echo signal, an output signal of the digitally controlled variable gain amplifier is an analog signal, and a signal received and transmitted by the digital preprocessing module 600 is a digital signal, so in the system, an analog-to-digital converter 301 is required to convert the analog signal and the digital signal, an input end of the analog-to-digital converter 301 is connected to an output end of the digitally controlled variable gain amplifier 200, an output end of the analog-to-digital converter 301 is connected to an input end of the digital preprocessing module 600, and the analog-to-digital converter 301 may convert an analog signal of the third echo signal transmitted by the digitally controlled variable gain amplifier 200 into a digital signal of the third echo signal, and transmits the converted digital signal of the third echo signal to the digital preprocessing module 600.
In this embodiment, if the variable gain amplifier in the laser radar ranging system is a digitally controlled variable gain amplifier, the converter includes an analog-to-digital converter, the analog-to-digital converter converts an analog signal of a third echo signal sent by the digitally controlled variable gain amplifier into a digital signal of the third echo signal, and sends the converted digital signal to the digital preprocessing module, and under the condition that the transmission power is not changed, the main controller can directly control the digitally controlled variable gain amplifier to adjust the gain of the second echo signal through a digital interface of the digitally controlled variable gain amplifier, so as to improve the dynamic range of the echo signal to be processed by the laser radar system, obtain the third echo signal, improve the ranging accuracy of the laser radar ranging system, and improve the ranging performance of the laser radar ranging system.
In the scenario that the digital time gain controller 400 adjusts the gain of the third echo signal according to the gain factor output by the main controller 500, the main controller 500 is configured to determine the gain factor according to a gain compensation curve or a statistical characteristic of the echo signal; the gain compensation curve is a curve obtained according to a theoretical optical path attenuation curve or a calibrated optical path attenuation curve.
Specifically, the main controller 500 may determine to adjust a gain coefficient of the third echo signal according to the gain compensation curve, output the determined gain coefficient, and control the digital time gain controller 400 to adjust the gain of the third echo signal. Optionally, the gain compensation curve may be a curve obtained according to the optical path attenuation curve, or may be a curve obtained according to a calibrated optical path attenuation curve. The calibrated optical path attenuation curve refers to an optical path attenuation curve obtained according to factory settings of the optical receiver, the horizontal axis of the optical path attenuation curve is the ranging distance of the target object, the vertical axis of the optical path attenuation curve is the echo energy of the echo signal, the closer the ranging distance of the target object is, the larger the value of the echo energy is, the farther the ranging distance of the target object is, and the smaller the value of the echo energy is. The main controller 500 may obtain a gain compensation curve according to the light path attenuation curve, where the closer the ranging distance of the target object is, the smaller the gain value is, and the farther the ranging distance of the target object is, the larger the gain value is. Alternatively, the main controller 500 may determine to adjust a gain coefficient of the third echo signal according to the statistical characteristics of the echo signals, output the determined gain coefficient, and control the digital time gain controller 400 to adjust the gain of the third echo signal. Optionally, the main controller 500 may determine that the digital time gain controller 400 adjusts the gain factor of the third echo signal according to the amplitude information of the echo signal and the waveform information of the echo signal. If the amplitude of the echo signal is higher and the waveform of the echo signal is larger, the main controller 500 may decrease the output gain factor; the main controller 500 may increase the gain factor of the output if the amplitude of the echo signal is lower and the waveform of the echo signal is smaller.
In this embodiment, the main controller determines to adjust a gain coefficient of the third echo signal according to a gain compensation curve or a statistical characteristic of the echo signal, controls the digital time gain controller to adjust a gain of the third echo signal, and improves a dynamic range of the echo signal to be processed by the laser radar system by adjusting the gain of the third echo signal in real time under the condition that the transmitting power is not changed, so that the ranging accuracy of the laser radar ranging system is improved, and the ranging performance of the laser radar ranging system is improved.
In the scenario that the optical detector 100 adjusts the gain of the first echo signal according to the bias control signal output by the master controller 500, the master controller 500 is configured to generate the bias control signal according to the characteristic of the optical detector 100 and the optical path attenuation characteristic; the characteristics of the light detector 100 are used to indicate the relationship between the received light power of the light detector 100 and the bias control signal.
Specifically, the main controller 500 generates a bias control signal for controlling the optical detector 100 to adjust the first echo signal according to the characteristics of the optical detector 100 and the optical path attenuation characteristics. Optionally, if the received optical power of the optical detector 100 is stronger and the degree of optical signal attenuation is weaker, the main controller 500 may generate a reduced value of the bias control signal; if the received optical power of the optical detector 100 is weaker and the optical signal is attenuated to a greater degree, the main controller 500 may generate an increased value of the bias control signal.
In this embodiment, the master controller generates a bias control signal for determining and adjusting the first echo signal according to the characteristics of the optical detector and the optical path attenuation curve, controls the optical detector to adjust the gain of the first echo signal, and under the condition that the transmitting power is not changed, the optical detector adjusts the gain of the first echo signal in real time, so that the dynamic range of the echo signal to be processed by the laser radar system is increased, the ranging precision of the laser radar ranging system is further increased, and the ranging performance of the laser radar ranging system is improved.
Fig. 5 is a schematic diagram of a lidar ranging system according to another embodiment. As shown in fig. 5, the system further includes a bias controller 700, wherein the bias controller 700 is connected to the main controller 500 and the light detector 100 respectively; the bias controller 700 is configured to generate an applied bias voltage according to the bias control signal output by the main controller 500, and transmit the applied bias voltage to the light detector 100; the optical detector 100 adjusts the gain of the first echo signal according to the applied bias voltage.
Specifically, lidar ranging system 10 further includes a bias controller 700, and bias controller 700 is connected to main controller 500 and light detector 100, respectively. The bias controller 700 generates an external bias voltage according to the bias control signal outputted from the main controller 500, and applies the external bias voltage to the optical detector 100, and the optical detector 100 adjusts the gain of the first echo signal according to the external bias voltage transmitted by the bias controller 700. Optionally, the bias controller 700 may generate an increased external bias value according to the signal for increasing the bias control output by the main controller 500, so that the optical detector 100 increases the gain of the first echo signal; the reduced applied bias value may also be generated according to the reduced bias control signal output by the main controller 500, so that the photodetector reduces the gain of the first echo signal.
In this embodiment, the lidar ranging system further includes a bias controller, the bias controller is connected with the master controller and the optical detector respectively, the bias controller generates an external bias according to a bias control signal output by the master controller, and transmits the external bias to the optical detector, so that the optical detector adjusts the gain of the first echo signal according to the external bias, under the condition that the transmitting power is not changed, the optical detector adjusts the gain of the first echo signal according to the external bias applied by the bias controller, the dynamic range of the echo signal to be processed by the lidar ranging system is improved, the ranging accuracy of the lidar ranging system is further improved, and the ranging performance of the lidar ranging system is improved.
Fig. 6 is a schematic diagram of a lidar ranging system according to another embodiment. As shown in fig. 6, the system further includes a ranging module 800 connected to the digital time gain controller 400; the ranging module 800 is configured to obtain ranging information according to the output signal of the digital time gain controller 400.
Specifically, the laser radar ranging system 10 further includes a ranging module 800 connected to the time gain controller 500, where the ranging module 800 obtains ranging information of the target object according to the third echo signal output by the digital time gain controller 400. Optionally, the ranging module 800 may obtain the ranging information of the target object according to information such as the amplitude of the third echo signal.
In this embodiment, laser radar ranging system still includes the range finding module of being connected with digital time gain control module, the range finding module obtains the range finding information of target object according to the third echo signal of digital time gain controller output, because the third echo signal is the echo signal that has passed through digital time gain controller processing, the range finding information that obtains according to the third echo signal is more accurate, the dynamic range of the echo signal that laser radar system will be handled has been improved, laser radar ranging system's range finding precision has been improved, laser radar ranging system's range finding performance has been promoted.
Fig. 7 is a schematic diagram of a lidar ranging system according to another embodiment. As shown in fig. 7, the system further includes an emission controller, emission hardware devices, emission optics, and a post-processing display module. The transmitting controller is respectively connected with the transmitting hardware equipment and the main controller, the transmitting optical device is connected with the transmitting hardware equipment, the post-processing display module is connected with the ranging module, the transmitting controller is used for sending control signals to the transmitting hardware equipment and sending synchronous signals to the main controller, the main controller is indicated to be capable of controlling the optical detector of the receiving link, the variable gain amplifier and the time gain controller, the transmitting hardware equipment is used for controlling the transmitting optical device to transmit laser radar signals according to the control signals sent by the transmitting controller, and the post-processing display module is used for processing and displaying ranging information of a target object acquired by the ranging module.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (10)
1. A lidar ranging system, the system comprising: the optical detector is connected with the variable gain amplifier, the converter is respectively connected with the variable gain amplifier and the digital time gain controller, and the main controller is respectively connected with the optical detector, the variable gain amplifier and the digital time gain controller; the optical detector is used for adjusting the gain of the first echo signal according to the bias control signal output by the main controller to obtain a second echo signal; the second echo signal is a current signal;
the variable gain amplifier is used for adjusting the gain of the second echo signal according to the gain value output by the main controller to obtain a third echo signal; the gain value is determined by the main controller according to a preset distance-gain compensation curve or a statistical characteristic value of an echo signal; the variable gain amplifier is an analog control variable gain amplifier or a digital control variable gain amplifier; the third echo signal is a voltage signal;
the digital time gain controller is used for adjusting the gain of the third echo signal according to the gain coefficient output by the main controller; the gain coefficient is determined by the main controller according to a gain compensation curve or the statistical characteristics of echo signals, and the gain compensation curve is obtained according to a light path attenuation curve or a calibrated light path attenuation curve.
2. The system of claim 1, wherein the statistical features comprise amplitude information of the echo signal and waveform information of the echo signal.
3. The system of claim 1 or 2, further comprising a digital pre-processing module connected to the converter and the digital time gain controller, respectively;
the digital preprocessing module is used for performing echo shaping processing on the third echo signal; the echo shaping process includes a digital filtering process and a baseline correction process.
4. The system of claim 3, wherein if the variable gain amplifier is an analog controlled variable gain amplifier, the converter comprises an analog-to-digital converter and a digital-to-analog converter;
the input end of the analog-to-digital converter is connected with the output end of the variable gain amplifier, and the output end of the analog-to-digital converter is connected with the input end of the digital preprocessing module;
the input end of the digital-to-analog converter is connected with the main controller, and the output end of the digital-to-analog converter is connected with the input end of the variable gain amplifier.
5. The system of claim 3, wherein if the variable gain amplifier is a digitally controlled variable gain amplifier, the converter comprises an analog-to-digital converter; the input end of the analog-to-digital converter is connected with the main controller, and the output end of the analog-to-digital converter is connected with the input end of the digital preprocessing module.
6. The system of claim 1 or 2, wherein the photodetector is any one of a diode, a diode array, a silicon photomultiplier, and a silicon photomultiplier array.
7. The system of claim 6, wherein the gain compensation curve is a curve derived from a theoretical optical path attenuation curve or a calibrated optical path attenuation curve.
8. The system of claim 1 or 2, wherein the master controller is configured to generate the bias control signal based on a characteristic of the light detector and an optical path attenuation characteristic; the characteristics of the photodetector are indicative of a relationship between the received optical power of the photodetector and the bias control signal.
9. The system of claim 1 or 2, further comprising a bias controller connected to the master controller and the light detector, respectively;
the bias controller is used for generating an external bias voltage according to the bias control signal output by the main controller and applying the external bias voltage to the light detector;
the photodetector adjusts the gain of the first echo signal according to the applied bias voltage.
10. The system of claim 1 or 2, further comprising a ranging module connected to the digital time gain controller; and the ranging module is used for acquiring ranging information according to the output signal of the digital time gain controller.
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| CN113625247B (en) * | 2021-10-11 | 2022-03-04 | 北京一径科技有限公司 | Control method and device and laser radar |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104737446A (en) * | 2012-10-24 | 2015-06-24 | 阿尔卡特朗讯公司 | Distance-based automatic gain control and proximity-effect compensation |
| CN106772437A (en) * | 2016-12-12 | 2017-05-31 | 中国科学院合肥物质科学研究院 | The laser radar apparatus of Self Adaptive Control dynamic range |
| CN107632307A (en) * | 2017-08-23 | 2018-01-26 | 天津大学 | Be self-regulated pulsed laser ranging system and method |
| CN207586422U (en) * | 2017-12-26 | 2018-07-06 | 成都心无界光电技术有限公司 | A kind of laser ranging system of total regulation |
-
2018
- 2018-11-19 CN CN201811376651.5A patent/CN111198381B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104737446A (en) * | 2012-10-24 | 2015-06-24 | 阿尔卡特朗讯公司 | Distance-based automatic gain control and proximity-effect compensation |
| CN106772437A (en) * | 2016-12-12 | 2017-05-31 | 中国科学院合肥物质科学研究院 | The laser radar apparatus of Self Adaptive Control dynamic range |
| CN107632307A (en) * | 2017-08-23 | 2018-01-26 | 天津大学 | Be self-regulated pulsed laser ranging system and method |
| CN207586422U (en) * | 2017-12-26 | 2018-07-06 | 成都心无界光电技术有限公司 | A kind of laser ranging system of total regulation |
Non-Patent Citations (3)
| Title |
|---|
| DPL固体激光成像雷达系统研究;杨志卿 等;《红外与激光工程》;20061031;第35卷;第299-303页 * |
| 基于数字信号处理技术的钢轨超声检测系统的研究;王勇;《中国优秀硕士学位论文全文数据库 工程科技II辑》;20060715;第58-59页 * |
| 脉冲激光测距接收电路的设计;张育琪 等;《电子科技》;20100430;第23卷(第4期);第30-32页 * |
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